Now players’ union chief Clarke Carlisle, chairman of the PFA, has called for football to “lower its ­tolerance” of the Neanderthal tendency before the game is shocked into restoring civilised standards by tragedy.

Carlisle, whose grasp of the game’s major issues has taken him to the top table on TV’s Question Time, has now warned that players’ safety was being taken for granted.

The York City defender said: “On one hand, you do not want to over-dramatise the problem and resort to scaremongering, but on the other hand you can’t sweep what happened at the Manchester derby under the carpet – because it was terrible.

“The truth about hooligan behaviour inside football grounds is not that it’s on the increase, nor that we are creeping back towards the bad old days, because the problem never went away in the first place.

“But the ­important thing is how we respond and deal with it.

“We don’t want football to reach the stage where ­something terrible happens before we address the issue, like tearing down the fences which penned in fans until 96 innocent people lost their lives at Hillsborough.

“And do we have to wait until an England captain is blinded by a coin to grasp the nettle and stamp down on supporters who behave in an unacceptable way?

“You can’t pretend there is no problem when one of England’s best players (Wayne Rooney) goes to take a corner and you can see missiles flying through the air around him.

“Until Rio Ferdinand was hit by that object, it’s only by luck that players have not been injured before because the missiles were missing their targets.

“Sadly, it has taken someone as high-profile as Rio to suffer for the issue to make the front pages. Now is the time to clamp down, now is the time to stamp it out.

“We need to lower our tolerance levels, we can’t afford to wait until there’s a tragedy.

“As an industry, we have started picking out individuals who make racist gestures or shout abuse which goes beyond the pale, so let’s root out the idiots who throw missiles or go on the pitch to confront players.

“The next set of TV rights is said to be worth £5billion to the Premier League.

“I don’t think it’s too much to ask for part of that astronomical sum to be set aside to make sure players are safe in their working environment – on the pitch – and fans can take their children to games in a healthy atmosphere.”

PFA chief executive Gordon Taylor has suggested mesh netting to separate fans from players in sensitive areas of the pitch, saying: “You have to consider putting up netting in vulnerable areas, around the corner flags and behind the goals.”

But Carlisle argued: “When we talk about putting up mesh netting, screens and so on, we are catering for the hooligan element and that’s the wrong option.

“If you treat fans like animals, and put them behind cages, it encourages some of them to behave like animals. We need to nullify their behaviour by weeding them out and catering for the decent, overwhelming majority.”